Telephone attachment.



P. A. JOHNSON.

TELEPHONE ATTACHMENT.

APPLIGATION FILED Nov. 12, 1912.

Patentedl Mar. 2, 1915.

2 SHEETS-SHEET 1.l

WHA/1555.55y

y 7'HE NRRIS PETERS CD., PHOTO-LITHO.. WSHINDTDN. D. C,

P. A. JOHNSON.

TELEPHONE ATTACHMENT.

APPLIGATION FILED Novdz, 1912.

Patented Mar. 2, 1915.

2 SHEETS-SHEET 2A SOS .w www.

WTNESSES Allorney TIE NDRRIS PETERS C0.A PHON-LITHD.. WASHINGTUN, D. C.

ysa

rn srnrns `TELEPHONE ATTACHMENT.

specification of Letters Patent.

Patented Mar. 2, 1915.

Applicationled November 12,1912. Serial No. 730,843. i

To all whom t may concern Be it known that I, PHILIP AuGUs'rUs JOHNSON,a citizen of the United States, residing at Springfield, in the countyof Lane and `State of Oregon, have invented new and useful Improvementsin Telephone Attachments, of which the yfollowing is a specification. fMy presentr invention relates to a telephone attachment particularlyadapted for use in connection with such apparatus forming Va part of asubscribers or'intercommunicating system, where it is possible for athird party to' overhearrconversations transpiring between two parties.

rIhe principal object of my invention is to provide means whereby suchinterloping, or attempt at eavesdropping may bedetected audibly in sucha manner that the particular apparatus from which the third partyinterferes, may be determined.

Further objects of my kinvention are to provide an attachment, embodyingmy invention, which may be easily installed in connection with existingtelephone apparatus; and, such apparatus that is simplein constructionand eflicient in action; l

A further object of' my invention is to provide means whereby it ismadenecessary to maintain the attachment in a good working condition, inorder to have the apparatus, to which'pit is attached, available forregular use. 4

Other objects of my 'inventionfwill appear in the following detaileddescription, taken in connection with the accompanying drawings formingapart of this specification, and in which drawing: f

Figurel is a compound viewv showing mechanism embodying my' invention,parts being shown in elevation and section, and circuitsdiagrammatically indicated. Fig. 2 is a cross sectional view on the line2--2 of Fig. 1'. Fig. 3 is-a perspective view of a switch used inconnection with the line wires `of the telephone system(- Similarcharacters refer to similar throughout thewviews,k

In ltelephone `systems of; the aforesaid type, it is comm'onpra'ctice todesignate for each apparatus, a certain number of rings of constant orvariable duration. For instance, one instrument may'lhave designatedtherefor, one long and two short rings, another, one short and two,'long rings, another, one long, a short, andt'w'o' long rings,

parts etc. Furthermore, each subscriber is furnished with a list of, oris familiar with the names of parties on the line, and the particular'combination of rings for their particular' apparatus. Itis with the viewof providing detection audibly, by aiparty, or parties, using thereceivers, when another apparatus is rendered active by removal of thereceiver from -the hook thereof, and by producing sonorous vibrations bythe lreceiver or receivers of the first mentioned apparatus, similar tothe rings designating the latter apparatus.

Having the foregoing in view, the attachment `comprises a movableelement 4k for carrying a plurality ofcontacts 5 spaced apa-rt from eachother, as by insulation 6, and any number and length, according to thering designating the particular apparatus to which it is attached. Inthe attachment as disclosed, it is designed for use in connection'withtelephone apparatus having designated thereto,fthe ring of one long, ashort and two long. The element 4 has therefore, successive contacts5'the first and latter two being longer than the second contact, asclearly shown in Fig. 1 ofthe drawing.'

The element 4 is preferably revoluble with a spindle 7, vcarriedlbyiframe-work 8, to be disposed in `a suitable housing, not shown inthe drawings. a

The 'usualireceiver hook' member 9 oscillatableabout pivot 110 andreceiver 11, normally-carried thereby, of a telephone apparatus, areshown, and ity is by movement of hook member 9, that movement-of element4 is controlled.A This` maybe accomplished by mechanism 'j designatedgenerally 'by'y 12,

which comprisesk an arm'13 rigid withhook member 9; a double armlever14, pivotally carried, in an insulated manner, by frame 8; va link 15operatively connecting arm 13 and one armV oflever 14 to oscillate thelatter by oscillation of hook'member 9, and

a pawl 15 movable with member 4, for engagement in a recess 16 in the'other arm of lever `14. The lever '14 may be convenientlytermed yanescapement, since it permits the elementy 4- to make one completerevolution at each actuationof member 9.

The pawlf15 may be carried by a 'disk 17, rigid on spindle?, so thatwhen hook 'member 9 is down, the recessed arm of lever 14 is positionedin the path of movement of membery 4, but allowing said latter member to:nove whenhook member 9 is raised, and

the ksaid'arm of lever 14 moved out of 'the path of movement of pawl-15, all as clearly shown in Fig. 1 of the'drawings'. f .f

As lmeans for imparting movement to member 4 when freed by movement-ofYmechanism 12, I provide a train of gears 18, including a main gear 19,actuated by a coil spring 20, of the type usually embodied inclock-Work; and, a vpinion 21 rigid with spindle 7 and which receivesits movement from gear 19. The other gears and pinions showmserve, as agovernor to prevent racingV of gear 19.- By this mechanism,the spring 20must be periodically wound, it vbeing understood that the spring expandsasv-it becomes unwound. v

For co-action with element 4 I provide a yieldable contact 22 which isdisposed in the path of movement of contacts 5, this contact formingpart of a circuit adapted to operatevmeans 23 rfor providing afluctuating current in the'line conductors 24 and 25 of the telephonesystem. This means 23 preferably comprises a spark coil 26, includingprimary and secondary-windings, a vibrator 27 being disposed in lthecircuit of the former; conductors 28 vand 29 operatively connect withlline conductors 24 and 25, reL

spectively, the conductor 28 having a spark Vgap 30 therein.,V One leadof the primary winding of spark coil 26, is conductively connected as byconductor 31 in contact with metallic frame'8, with the member 4. TheotherV lead is conductively connected with one pole of an electricgenerator 32, as by conductor 33, the other pole of said generator beingconductively connected, `.to 'conf ductor 35, withyieldable contact 22,so that When-contact 22 engages with yone' of the contacts 5, a completecircuitl is Vprovided through the primary winding of coil 26,

causing fluctuations atk gap 30 responsive ,to vibrator 27.. It will bereadily perceived, that the -iiuctuations at gap 30 will'producesonorous vibration by the diaphragms of the receivers oii their hooks.Itwill be further perceived, that the duration ofthis sonorous vibrationwill be according to the length of time contact 22 engages with one ofthe contacts 5, and this engagement is dependent upon the length ofsuchparticular contact.

vThat the attachment must be maintained in a workingl condition in sofar as mechanism 18 is concerned, I dispose a switch 36 in one of theline conductors (that designated 25), this switchbeing normally heldclosed, as by a spring 37. An arm 38 movablycarried by frame 8, and,insulated from Vsaid switch 36, in any suitable manner, extends so astobe acti'iated-when spring 2O expands toV a predetermined extent, theswitch being opened -by saidk actuation; Thus, as spring 20 is about tobecome weak infits ability to'rotate-gear 19, the switch 20-willbeopened rendering the particular apparatus with which the attachment isassociated, inoperative, untilthe spring 20 is rewound, whereupon i thesaid switch is closed responsive to action of spring 37.

" The operation of the attachment is as follows: Assuming two partiesarevusing the line conductors of the telephone system, and

ay third partyremoves the receiver, such as is shown in Fig. 1 of thedrawing. This action allows hook member v9'to move upwardly, actuatingescapement lever 14, and freeingmember 4 to move responsive to mechanism18. As soon asyieldable contact V22 engages with one of the contacts 5,a ciri cuit is completed through the'primary winding of coil 26,actuating vibrator 27. This complete circuit induces a currentl to betransmitted through conductors 28 and29, r with fluctuations at sparkgap 30, responsive -f 1 t0 actuation of vibrator 27. These fluctuationsare very rapid, and continue until the element 4 moves so that contact22 no longer engages with one of its contacts.- In the exampleshown,'the seriesof sonorous vibraii;

tions, produced throughvelement 4, will be of one longone short Aand twolong durations. Inasmuch as parties using-the line conductors, haverendered their receivers operative, they can detect from Vthe sonorousvibrations, the particular apparatus which has been rendered operativeand available for interloping 'or eavesdropping.

Y Changes in 4details may be made without i departing from the spirit orscope of my invention; but, f v 1 1. In an apparatus of the characterdescribed, the combination with line conduc tors and a receiver hookmember, of an element having a plurality of contacts, a second contacthaving engagement with contacts of said element, said element and secondcontact being movable one with respect to the other, a device forproducing fluctuating current in said line conductors, operable uponcompletion of acircuit through'anyv of the contacts of said element andsaid second contact, a windable spring motor for producing relativemovement between said element and second contact when the said receiv'erhook member is moved in one direction, and means for breaking thecircuit of said line conductors lwhen said motor becomesunwound to apredetermined extent.k `f

ond contact for engagement with contacts o fsaidelement, said elementand second iis f izo iras

contact beingmovable one with respect to the other, a device-forproducing fluctuating currents in said line conductors, operable uponcompletion of a circuit through any ofthe contacts ofsaid element andsaid sec-y ond contact, a cut out switch in one of said line conductors,normally closed, coil spring operated means for producing movement ofsaid element and second contact, one relative to the other, when saidreceiver hook is moved in one direction, and means operatively connectedwith said switch and cooperating with said coil spring to open saidswitch when said spring is unwound to ay predetermined extent.

3. In an apparatus of the character described, the combination with lineconductors and a receiver hook member, of a revoluble member having aplurality of contacts spaced apart from each other; a second contact forengagement with the said contacts of said revoluble member; a spark coilincluding primary and secondary windings, and a circuit breaker; anelectric generator; means providing a circuit including said revolubleelement, second contact, electric generator and the said primary windingof said spark coil; means having a spark gap conductively connecting theleads of the secondary winding of said spark with said line terminals;and, means eiecting rotation of' said revoluble element when said hookmember is raised from a. normal position.

4,-. In an apparatus ofthe character described, the combination with'line conductors and a receiver hook member, of an element having-aplurality of contacts; a second contact for engagement with contacts ofsaid element, said element and second contact being movable one withrespect to the other; a spark coil including primary and secondarywindings, and, a circuit breaker; an electric generator; means pro-Copies of this patent may be obtained for viding a circuit includingsaid element having a plurality of contacts, second contact, electricgenerator and the said primary winding of said coil; means having aspark gap conductively connecting the leads of the said secondarywinding of said spark coil with said line terminals; and, meanseffecting movement of said element and second contact, one relative tothe other, when said receiver hook member is moved from a normalposition. l

5. In an apparatus of the character described, the combination with lineconductors and a receiver-hook member, of a revolubly mounted elementhaving a plurality 4of contacts, a motor for intermittently revolvingsaid element, a pawl revoluble with said element, an escapement memberadapted to be actuated by removal and replacement of a receiver withrespect to said receiver-hook member and mounted to operatecooperatively with said pawl and to free said pawl for the revolution ofsaid element through power derived from vsaid motor upon the removal ofthe receiver from the hook, Va second contact for engagement with thecontact of said revoluble element upon turning movement of the same,means for producing a current, and means to cause a iiuctuation of saidcurrent in its passage as a circuit is completed through any one of thecontacts of said revoluble element and said second contact.

CHAS. L. SCOTT, E. C. BAKER.

ve cents each, by addressing the Commissioner of Patents.

Washington, D. C.

